In general, audience ratings are measured by broadcast stations or the like in order to check the popularity of predetermined programs being broadcasted by themselves, reflect on the production of next programs, and determine programs to be produced.
For a method of measuring audience ratings, there have been known various methods such as, a direct survey method for presenting a list of broadcast programs to a sample group to measure audience ratings, an over-the-phone survey method for making calls to viewers to measure program ratings currently being viewed at the time of broadcasting predetermined programs, a diary-type method for presenting a daily broadcast list for a specific period to the same panel each time and allowing viewers of the panel to directly write the viewed contents, and a meter-type method for measuring when and which channels have been set by predetermined generations using a mechanical device.
However, the forgoing survey methods have a problem in which audience ratings cannot be measured for viewers over a wide range of regions but only measured for those in a specific region, and the number of viewers who are subject to the audience measurement is too small if audience ratings are measured in real-time, and the reliability of measured audience ratings is very low if audience ratings are not measured in real-time.
Furthermore, since the appearance of automatic response systems, audience ratings have been measured by notifying an ARS phone number to viewers through television broadcast signals and then allowing viewers responding to an audience measurement to make phone calls. It makes possible to measure audience ratings for viewers over a wide range of regions, but on the contrary, has a difficulty that all television broadcast stations should notify their ARS phone numbers to viewers through television broadcast signals and also viewers should individually make phone calls.